PHP Header redirect not working

include('header.php');


$name
            = $_POST['name'];
$score = $_POST['score'];
$dept =
            $_POST['dept'];

$MyDB->prep("INSERT INTO demo
            (`id`,`name`,`score`,`dept`, `date`) VALUES
            ('','$name','$score','$dept','$date')");
// Bind a value to our :id
            hook
// Produces: SELECT * FROM demo_table WHERE id =
            '23'
$MyDB->bind(':date', $date);
// Run the
            query
$MyDB->run();


header('Location:index.php');

            exit;

The above code
keeps giving me an issue with the redirect. The error is the following:

Warning: Cannot
modify header information - headers already sent by (output
started at
/Applications/MAMP/htdocs/testygubbins/OO/test/header.php:15) in


/Applications/MAMP/htdocs/testygubbins/OO/test/form.php on line
16.

I am totally
flummoxed by this. Does anyone know what I should be doing to make it
work?

EDIT

header.php
code:

include('class.user.php');
include('class.Connection.php');

$date
            =
            date('Y-m-j');

?>



            

            



            id="page">

class="post-text" itemprop="text">

class="normal">Answer

Look
carefully at your includes - perhaps you have a blank line after a closing ?>
?

This will cause some literal whitespace to be
sent as output, preventing you from making subsequent header calls.

Note that it is legal to leave the close ?>
off the include file, which is a useful idiom for avoiding this
problem.

(EDIT: looking at
your header, you need to avoid doing any HTML output if you want to output headers, or
use output buffering to capture
it).

Finally, as the href="http://php.net/header" rel="noreferrer">PHP manual page for header
points out, you should really use full URLs to
redirect:

Note:
HTTP/1.1 requires an absolute
URI as argument to
Location:
including the scheme, hostname and

absolute path, but some clients accept

relative URIs. You can
usually use
$_SERVER['HTTP_HOST'],
$_SERVER['PHP_SELF'] and
dirname() to
make an absolute URI from a relative
one
yourself: